un·​treat·​ed | \ ˌən-ˈtrē-təd How to pronounce untreated (audio) \

Definition of untreated

: not treated untreated wastewater especially : not improved or controlled medically an untreated case of pneumonia untreated diabetic patients

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Examples of untreated in a Sentence

Recent Examples on the Web Left untreated, the autoimmune disorder can lead to permanent joint damage, which is why early care is so important, according to the Mayo Clinic. Joni Sweet, SELF, "Psoriatic Arthritis Medication: What You Need to Know," 13 Nov. 2020 Patients often arrive at county jails with existing medical or mental health issues, including addictions, that in some cases have gone untreated for years. Jeff Mcdonald, San Diego Union-Tribune, "Sheriff met privately with healthcare contractor months before inviting bids," 1 Nov. 2020 Doctors diagnosed the 65-year-old with a severe internal hernia, which can be life threatening if left untreated, and rushed him into surgery that day. Torey Van Oot Star Tribune, Star Tribune, "Minnesota U.S. Senate candidate Jason Lewis released from hospital after emergency surgery," 28 Oct. 2020 An infamous example is the Tuskegee experiments starting in the 1930s where Black men with syphilis were left untreated as part of an experiment to study the symptoms of the disease. Amber Randall, sun-sentinel.com, "A South Florida COVID-19 vaccine trial is recruiting minority participants. Will it be successful?," 6 Oct. 2020 Recently, many of Hoopes’ furry patients have come to him with a relatively common oral cancer that will almost certainly kill them within a few months if left untreated. Daniel Oberhaus, Wired, "A Common Plant Virus Is an Unlikely Ally in the War on Cancer," 5 Oct. 2020 If left untreated, for example, diabetes increases the risk of congenital abnormalities from 3 percent to as high as 25 percent. Jyoti Madhusoodanan/undark, Popular Science, "How do we know if medicines are safe during pregnancies?," 2 Oct. 2020 If left untreated, Lyme disease can cause severe joint pain and swelling, particularly in the knees and other large joints. Jennifer King Lindley, Good Housekeeping, "The Science of Joint Health," 1 Oct. 2020 Smith-Whitley said that, too, is a potentially fatal complication if left untreated. NBC News, "Throughout pandemic, sickle cell patients suffer quietly at home," 28 Sep. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'untreated.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of untreated

15th century, in the meaning defined above

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Time Traveler for untreated

Time Traveler

The first known use of untreated was in the 15th century

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Statistics for untreated

Last Updated

17 Nov 2020

Cite this Entry

“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 25 Nov. 2020.

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More Definitions for untreated


How to pronounce untreated (audio)

English Language Learners Definition of untreated

: not getting medical care : without medical treatment
: not made better or safer by being treated with a chemical or other substance


un·​treat·​ed | \ -ˈtrēt-əd How to pronounce untreated (audio) \

Medical Definition of untreated

: not subjected to treatment an untreated disease

More from Merriam-Webster on untreated

Thesaurus: All synonyms and antonyms for untreated

Nglish: Translation of untreated for Spanish Speakers

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